Ethnopharmacology of medicinal plants of carrasco, northeastern Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

The goal of this study was to conduct an ethnobotanical survey of medicinal species from the carrasco vegetation of the Araripe National Forest, state of Ceará, Brazil, as well as determining species with bioprospecting potential

MATERIALS AND METHODS

The ethnobotanical data were collected through semi-structured interviews and a free list. The relative importance of the plants cited was assessed, as well as species that stood out with respect to bodily systems, on the basis of informant consensus.

RESULTS

A total of 32 species belonging to 29 genera and 20 families were recorded. Of this total, six species (19%) showed great versatility regarding their uses in regard to up to seven bodily systems. The therapeutic indications were grouped into 14 categories of bodily systems. Circulatory and genitourinary disorders, endocrine, nutritional and metabolic diseases, and undefined pain or disease showed the greatest consensus between informants.

CONCLUSIONS

Ximenia americana, Himathantus drasticus, Stryphnodndron rotundifolium, Bowdichia virgilioides, and Hymenaea courbaril were the species warranting more in-depth study, on the basis of versatility and informant consensus on the uses of the species.

Ethnopharmacological study of plants sold for therapeutic purposes in public markets in Northeast Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

Studies of ethnobiological nature favor the rescue of popular culture, preventing important cultural and biological information from being lost over time. Another interesting point is that it can support bioprospecting studies focusing on the discovery of new drugs.

OBJECTIVE OF THE STUDY

Our aim was to conduct a survey of plants sold for therapeutic purposes in public markets in the Crajubar Triangle in Northeast Brazil.

MATERIALS AND METHODS

Using a questionnaire, data were collected regarding the part of the plant used, method of preparation, quantity needed, instructions for use and known adverse effects. From the data obtained, we calculated the relative importance of species and informant consensus factor.

RESULTS

Vendors indicated 91 useful species from a therapeutic point of view, distributed in 49 plant families. The preparation methods most frequently mentioned by informants were decoction, infusion, sauce with part of the plant in water and lozenge. The informants of this study mentioned bark, leaves, seeds and roots as parts of the plant most sold for therapeutic use. Disorders of the digestive system was the disease/disorder category with the highest consensus among the vendors, and the species Ximenia americana, Lippia gracillis, Stryphnodendron rotundifolium, Anacardium occidentale, Hymenaea courbail, Myracrodruon urundeuva, Amburana cearensis and Himatanthus drasticus were the most versatile among the plants sold in markets.

CONCLUSIONS

Vendors indicated 91 species belonging to 49 botanical families and 89 genera. The most frequent forms of preparation were decoction, infusion and sauce made with part of the plant in water. The most common form of administration was oral. Bark and leaves were the plant parts most used. Thirteen species showed great versatility regarding their use. We noted 291 indications for use in 13 disease/disorder categories.

Essential Oils and Their Major Compounds in the Treatment of Chronic Inflammation: A Review of Antioxidant Potential in Preclinical Studies and Molecular Mechanisms

Inflammatory diseases result from the body's response to tissue damage, and if the resolution is not adequate or the stimulus persists, there will be progression from acute inflammation to chronic inflammation, leading to the development of cancer and neurodegenerative and autoimmune diseases. Due to the complexity of events that occur in inflammation associated with the adverse effects of drugs used in clinical practice, it is necessary to search for new biologically active compounds with anti-inflammatory activity. Among natural products, essential oils (EOs) present promising results in preclinical studies, with action in the main mechanisms involved in the pathology of inflammation. The present systematic review summarizes the pharmacological effects of EOs and their compounds in in vitro and in vivo models for inflammation. The research was conducted in the following databases: PubMed, Scopus, BIREME, Scielo, Open Grey, and Science Direct. Based on the inclusion criteria, 30 articles were selected and discussed in this review. The studies listed revealed a potential activity of EOs and their compounds for the treatment of inflammatory diseases, especially in chronic inflammatory conditions, with the main mechanism involving reduction of reactive oxygen and nitrogen species associated with an elevation of antioxidant enzymes as well as the reduction of the nuclear factor kappa B (NF-κB), reducing the expression of proinflammatory cytokines. Thus, this review suggests that EOs and their major compounds are promising tools for the treatment of chronic inflammation.

Promising medicinal plants for bioprospection in a Cerrado area of Chapada do Araripe, Northeastern Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medical systems represent an important source of knowledge about the use of biodiversity. Ethnobotanical and ethnopharmacological studies can encourage bioprospecting in the pursuit and selection of promising medicinal plants. This study investigated the diversity of medicinal plants in a disjunct area of cerrado in Chapada do Araripe, Ceará, Brazil, and assessed the species of interest for bioprospecting.

MATERIALS AND METHODS

Structured and semi-structured interviews were conducted through free listing, and the informants were recruited using the "snowball" technique. The relative importance and informant consensus factor were analyzed for the selection of plant species with therapeutic potential.

RESULTS

A total of 68 species were recorded and cited for 91 therapeutic purposes. Of these, 10 species showed great versatility of use, including Copaifera langsdorffii Desf., Caryocar coriaceum Wittn., Himatanthus drasticus (Mart.) Plumel, Stryphnodendron rotundifolium Mart., and Dimorphandra garderiana Tull. The therapeutic citations were grouped into 16 categories of body systems, of which Injuries, Poisonings and Other Consequences of External Causes, and Neoplasias showed the highest agreement of use.

CONCLUSIONS

Regarding the diversity of the species, some including Tocoyena Formosa (Cham. & Schlecht.) Schum., Himatanthus drasticus, Caryocar coriaceum, Roupala montana Aubl. and Stryphnodendron rotundifolium showed both high relative importance and strong consensus among informants, and although many have already been investigated scientifically, others are almost unknown with respect to their medicinal properties and can be targets for bioprospecting.

In vitro antimicrobial and modulatory activity of the natural products silymarin and silibinin

Silymarin is a standardized extract from the dried seeds of the milk thistle (Silybum marianum L. Gaertn.) clinically used as an antihepatotoxic agent. The aim of this study was to investigate the antibacterial and antifungal activity of silymarin and its major constituent (silibinin) against different microbial strains and their modulatory effect on drugs utilized in clinical practice. Silymarin demonstrated antimicrobial activity of little significance against the bacterial strains tested, with MIC (minimum inhibitory concentration) values of 512 µg/mL. Meanwhile, silibinin showed significant activity against Escherichia coli with a MIC of 64 µg/mL. The results for the antifungal activity of silymarin and silibinin demonstrated a MIC of 1024 µg/mL for all strains. Silymarin and silibinin appear to have promising potential, showing synergistic properties when combined with antibacterial drugs, which should prompt further studies along this line.

In vitro and in silico inhibitory effects of synthetic and natural eugenol derivatives against the NorA efflux pump in Staphylococcus aureus

Staphylococcus aureus is a Gram-positive bacterium responsible for a number of diseases and has demonstrated resistance to conventional antibiotics. This study aimed to evaluate the antibacterial activity of eugenol and its derivatives allylbenzene, 4-allylanisole, isoeugenol and 4-allyl-2,6-dimethoxyphenol against the S. aureus NorA efflux pump (EP) in association with norfloxacin and ethidium bromide. The antibacterial activity of the compounds was assessed using the broth microdilution method to determine the minimum inhibitory concentration (MIC). A reduction in the MIC of ethidium bromide (a substrate for several efflux pumps) or norfloxacin was used as a parameter of EP inhibition. Molecular modeling studies were used to predict the 3D structure and analyze the interaction of selected compounds with the binding pocket of the NorA efflux pump. Except for 4-allylanisole and allylbenzene, the compounds presented clinically effective antibacterial activity. When associated with norfloxacin against the SA 1199B strain, 4-allyl-2,6-dimethoxyphenol eugenol and isoeugenol caused significant reduction in the MIC of the antibiotic, demonstrating synergistic effects. Similar effects were observed when 4-allyl-2,6-dimethoxyphenol, allylbenzene and isoeugenol were associated with ethidium bromide. Together, these findings indicate a potential inhibition of the NorA pump by eugenol and its derivatives. This in vitro evidence was corroborated by docking results demonstrating favorable interactions between 4-allyl-2,6-dimetoxypheno and the NorA pump mediated by hydrogen bonds and hydrophobic interactions. In conclusion, eugenol derivatives have the potential to be used in antibacterial drug development in strains carrying the NorA efflux pump.

Plant species as a therapeutic resource in areas of the savanna in the state of Pernambuco, Northeast Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

Ethnobotanical studies have contributed significantly in research of plants with therapeutic potential. The aim of the present study was to learn about the use of native medicinal plants cited by the traditional population in "cerradão" (savanna woodland) areas in Northeast Brazil, providing data on therapeutic indications of the species used and their versatility.

MATERIALS AND METHODS

Semi-structured interviews were conducted on the basis of a standardized questionnaire designed for key informants selected using the "snowball" technique. The selection of plants species with therapeutic potential was performed on the basis of the relative importance (RI) and informant consensus fator (ICF).

RESULTS

A total of 78 species were indicated for 87 therapeutic purposes. Of these, 11 species presented great versatility of use (RI>1), as e.g.including Copaifera langsdorffii Desf., Hybanthus calceolaria (Mart.) Plumel., Heliotropium cf. indicum L., Croton zehntneri, Croton heliotropiifolius, Myracrodruon urundeuva, Stryphnodendro rotundifolium. Medicinal uses could be generalized Pax & K. Hoffm and Hymenaea courbaril L. The therapeutic indications were grouped into 14 use 15 categories with 594 species-category combinations. The largest number of medicinal species was indicated for illnesses or undefined pain, followed by diseases associated with respiratory, digestive and genitourinaryof body systems. The factor informant consensus highlighted the agreement in the use of plants and showed that the, of which Diseases of the Nervous System and, Diseases of the Circulatory System had the greatest agreement 1.0 and 0.87 repectively, Disorders of the Visual Sensory System - Eyes and Respiratory System Disorder showed the highest agreement of use.

CONCLUSIONS

Most of the species cited by the key informants are well known scientifically, but it is interesting that some have been studied little or not all with regard to confirming their purported medicinal properties and can contribute substantially to pharmacological and phytochemical investigations in the search for new drugs.

Effect of Carvacrol and Thymol on NorA efflux pump inhibition in multidrug-resistant (MDR) Staphylococcus aureus strains

Undue exposure to antimicrobials has led to the acquisition and development of sophisticated bacterial resistance mechanisms, such as efflux pumps, which are able to expel or reduce the intracellular concentration of various antibiotics, making them ineffective. Therefore, inhibiting this mechanism is a promising way to minimize the phenomenon of resistance in bacteria. In this sense, the present study sought to evaluate the activity of the Carvacrol (CAR) and Thymol (THY) terpenes as possible Efflux Pump Inhibitors (EPIs), by determining the Minimum Inhibitory Concentration (MIC) and the association of these compounds in subinhibitory concentrations with the antibiotic Norfloxacin and with Ethidium Bromide (EtBr) against strains SA-1199 (wild-type) and SA-1199B (overexpresses NorA) of Staphylococcus aureus. In order to verify the interaction of the terpenes with the NorA efflux protein, an in silico molecular modeling study was carried out. The assays used to obtain the MIC of CAR and THY were performed by broth microdilution, while the Efflux Pump inhibitory test was performed by the MIC modification method of the antibiotic Norfloxacin and EtBr. docking was performed using the Molegro Virtual Docker (MVD) program. The results of the study revealed that CAR and THY have moderate bacterial activity and are capable of reducing the MIC of Norfloxacin antibiotic and EtBr in strains of S. aureus carrying the NorA efflux pump. The docking results showed that these terpenes act as possible competitive NorA inhibitors and can be investigated as adjuvants in combined therapies aimed at reducing antibiotic resistance.

Nootkatone Inhibits Acute and Chronic Inflammatory Responses in Mice

Nootkatone (NTK) is a sesquiterpenoid found in essential oils of many species of Citrus (Rutaceae). Considering previous reports demonstrating that NTK inhibited inflammatory signaling pathways, this study aimed to investigate the effects of this compound in mice models of acute and chronic inflammation. Murine models of paw edema induced by carrageenan, dextran, histamine, and arachidonic acid, as well as carrageenan-induced peritonitis and pleurisy, were used to evaluate the effects of NTK on acute inflammation. A murine model of granuloma induced by cotton pellets was used to access the impact of NTK treatment on chronic inflammation. In the acute inflammation models, NTK demonstrated antiedematogenic effects and inhibited leukocyte recruitment, which was associated with decreased vascular permeability, inhibition of myeloperoxidase (MPO), interleukin (IL)1-β, and tumor necrosis factor (TNF)-α production. In silico analysis suggest that NTZ anti-inflammatory effects may also occur due to inhibition of cyclooxygenase (COX)-2 activity and antagonism of the histamine receptor type 1 (H1). These mechanisms might have contributed to the reduction of granuloma weight and protein concentration in the homogenates, observed in the chronic inflammation model. In conclusion, NTK exerted anti-inflammatory effects that are associated with inhibition of IL1-β and TNF-α production, possibly due to inhibition of COX-2 activity and antagonism of the H1 receptor. However, further studies are required to characterize the effects of this compound on chronic inflammation.

Possible involvement of transcriptional activation of nuclear factor erythroid 2-related factor 2 (Nrf2) in the protective effect of caffeic acid on paraquat-induced oxidative damage in Drosophila melanogaster

Paraquat (PQ) is a widely used herbicide with no antidote which is implicated in the pathogenesis of the Parkinson's disease. The present study then investigated the potential of caffeic acid (CA), a known antioxidant, cardioprotective and neuroprotective molecule to counteract oxidative stress mediated by PQ. In addition, molecular docking was performed to understand the mechanism underlying the inhibitory effect of CA against PQ poisoning. The fruit fly, Drosophila melanogaster, was exposed to PQ (0.44 mg/g of diet) in the absence or presence of CA (0.25, 0.5, 1 and 2 mg/g of died) for 7 days. Data showed that PQ-fed flies had higher incidence of mortality which was associated with mitochondrial dysfunction, increased free Fe(II) content and lipid peroxidation when compared to the control. Co-exposure with CA reduced mortality and markedly attenuated biochemical changes induced by PQ. The mechanism investigated using molecular docking revealed a strong interaction (-6.2 Kcal/mol) of CA with D. melanogaster transcriptional activation of nuclear factor erythroid 2-related factor 2 (Nrf2). This was characterized by the binding of CA to keap-1 domain of Nrf2. Taking together these results indicate the protective effect of CA against PQ-induced oxidative damage in D. melanogaster was likely through its coordination which hinders Nrf2-keap-1 binding leading to an increase of the antioxidant defense system.

Attenuation of visceral nociception by α-bisabolol in mice: investigation of mechanisms

Background

We previously described the visceral antinociceptive property of α-bisabolol (BISA) in mouse models of visceral nociception induced by cyclophosphamide and mustard oil (MO). This study examined the effect of BISA in mouse models of visceral nociception induced by acetic acid, capsaicin, formalin, and the contribution of the nitric oxide system, α₂, K_ATP, 5-HT₃ and TRPV1 receptors to the effect of BISA on MO-evoked nociceptive behaviors. Mice were pretreated orally with BISA (50, 100 and 200 mg/kg) or vehicle, and the pain-related behavioral responses to intraperitoneal administration of acetic acid or intracolonic injection of MO were analyzed.

Results

BISA significantly suppressed the nociceptive behaviors in a dose-unrelated manner. The antinociceptive effect of BISA (50 mg/kg) was show to be glibenclamide resistant, but it was not blocked by pretreatment with the other antagonists tested. In the open-field test that detects sedative or motor abnormality, mice received 50 mg/kg BISA did not show any per se influence in ambulation frequency.

Conclusions

However, their precise antinociceptive mechanisms of action have not been determined.

Gastroprotective and ulcer healing effects of essential oil of Hyptis martiusii Benth. (Lamiaceae)

Hyptis martiusii Benth. is an aromatic plant found in abundance in northeastern Brazil that is used in ethnomedicine to treat gastric disorders. The aim of this study was to elucidate the mechanisms of action involved in the gastroprotection of the essential oil of Hyptis martiusii (EOHM) and to evaluate its healing capacity. Wistar rats were exposed to different protocols and subsequently were treated with 1% Tween-80 aqueous solution (negative control), pantoprazole, carbenoxolone, N-acetylcysteine (depending on the specificity of each model) or EOHM. The antisecretory activity (basal or stimulated) was determined using the pyloric ligature method. The gastroprotective action of nitric oxide and sulphydryl groups (–SH groups), as well as the quantification of adherent mucus and the levels of malondialdehyde and –SH groups in gastric mucosa, were evaluated using ethanol-induced gastric ulcer model. The healing ability was evaluated using the acetic acid-induced gastric ulcer model and histological and immunohistochemical analysis (HE, PAS and PCNA). EOHM (400 mg/kg) reduced the volume and acidity of gastric secretion stimulated by histamine and pentagastrin. The gastroprotective effect of EOHM involves the participation of endogenous sulfhydryl groups. EOHM increased mucus production (54.8%), reduced levels of MDA (72.5%) and prevented the depletion of –SH groups (73.8%) in the gastric mucosa. The treatment with EOHM reduced in 70.3% the gastric lesion area, promoting significant regeneration of the gastric mucosa, as confirmed by histological analysis and analysis of proliferating cell nuclear antigen. The results show that gastroprotective effect of EOHM is mediated by cytoprotective and antioxidant mechanisms and by their antisecretory activity, and suggest that the essential oil of Hyptis martiusii is a promising candidate for the treatment of gastric ulcers.

Biological properties of terpinolene evidenced by in silico, in vitro and in vivo studies: A systematic review

BACKGROUND

Terpinolene, a monoterpene that is naturally found in a variety of herbs, is widely used as a flavoring agent in the industry. Although it's well established in the literature that terpinolene is an important component of plant extracts, the biological properties and the potential therapeutic use of this compound remain poorly explored.

PURPOSE

This work aimed to answer the following guiding question: "What are the biological activities of terpinolene demonstrated through in silico, in vitro, and in vivo assays?".

STUDY DESIGN AND METHODOLOGY

A systematic review was carried out in four electronic databases (Embase, Web of Science, Scopus, and PubMed) according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, using the following search terms: terpinolene "AND" activity "OR" properties "OR" therapeutic "OR" treatment. This search included manuscripts published between 1960 and June 2020. Study selection was conducted by two independent reviewers according to predefined criteria.

RESULTS

The initial search found a total of 2449 articles. However, only 57 of them were selected as they met the inclusion criteria and answered the guiding question. The analysis of these studies indicated that terpinolene presents a series of biological effects, from which the antioxidant, larvicide, and insecticide activities stand out. Despite the evidence demonstrating that terpinolene has the potential to be used in a broad pharmacological context, the mechanisms underlying its cellular and molecular effects remain to be better elucidated. In addition, the in vivo efficacy and safety of the administration of this compound have been poorly evaluated through either preclinical and clinical trials. Therefore, this study highlights the importance of characterizing the biological aspects and mechanisms of action of this natural compound.

CONCLUSION

The data summarized in the present systematic review demonstrates the pharmacological potential of terpinolene. Nevertheless, most studies included in this review provide a superficial characterization of terpinolene biological effects and therefore, further research elucidating its mechanism of action and potential therapeutic benefits through preclinical and clinical trials are required. Nevertheless, due to its wide range of different biological activities, terpinolene will certainly attract the interest of scientific research, which could significantly contribute to the development of new products with both therapeutic and environmental applications.

In Vitro and In Silico Inhibition of Staphylococcus aureus Efflux Pump NorA by α-Pinene and Limonene

Since the discovery of the first antibiotics, bacteria have acquired a variety of resistance mechanisms, with efflux pump (EP) being the most prominent mechanism for intracellular targeting drugs. These proteins have become efficient mechanisms of resistance to antibiotics in species such as Staphylococcus aureus and, therefore, have been identified as promising therapeutic targets in antibacterial drug development. Accordingly, evidence suggests that monoterpenes can act as EP inhibitors and can be useful in circumventing bacterial resistance. This study aimed to evaluate the effectiveness of monoterpenes α-pinene and limonene as EP inhibitors against a strain of S. aureus expressing NorA protein. The minimum inhibitory concentration (MIC) against the 1199B strain of S. aureus, which carries genes encoding efflux proteins associated with antibiotic resistance to norfloxacin, was assessed through the broth microdilution method. The results obtained served as a subsidy for the analysis of the NorA pump inhibition with norfloxacin and ethidium bromide. Docking techniques, in silico, were used to evaluate the interaction of monoterpenes with NorA. Both monoterpenes showed no clinically effective antibacterial activity. Nevertheless, these compounds were found to decrease the MICs of ethidium bromide and norfloxacin indicating EP inhibition, which was confirmed by molecular docking analyses. In conclusion, α-pinene and limonene showed promising antibiotic-enhancing properties in S. aureus 1199B strain, indicating that monoterpenes can be used in targeted drug development to combat antibiotic resistance associated with EP expression.

Evaluation of the Antifungal Activity of the Licania Rigida Leaf Ethanolic Extract against Biofilms Formed by Candida Sp. Isolates in Acrylic Resin Discs

Candida sp. treatment has become a challenge due to the formation of biofilms which favor resistance to conventional antifungals, making the search for new compounds necessary. The objective of this study was to identify the composition of the Licania rigida Benth. leaf ethanolic extract and to verify its antifungal activity against Candida sp. and its biofilms. The composition identification was performed using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) technique. The antifungal activity of extract and fluconazole against planktonic cells and biofilms was verified through the minimum inhibitory concentration (MIC) following biofilm induction and quantification in acrylic resin discs by reducing tetrazolic salt, with all isolates forming biofilms within 48 h. Six constituents were identified in the extract, and the compounds identified are derivatives from phenolic compounds such as flavonoids (epi) gallocatechin Dimer, epigallocatechin and gallocatechin, Myricetin-O-hexoside, Myricitrin, and Quercetin-O-rhamnoside. The extract reduced biofilm formation in some of the strains analyzed, namely C. tropicalis URM5732, C. krusei INCQS40042, and C. krusei URM6352. This reduction was also observed in the treatment with fluconazole with some of the analyzed strains. The extract showed significant antifungal and anti-biofilm activities with some of the strains tested.

ETHNOBIOLOGICAL SURVEY OF PLANTS AND ANIMALS USED FOR THE TREATMENT OF ACUTE RESPIRATORY INFECTIONS IN CHILDREN OF A TRADITIONAL COMMUNITY IN THE MUNICIPALITY OF BARBALHA, CEARÁ, BRAZIL

BACKGROUND

The use of natural resources for the treatment of acute respiratory infections in children is a widespread practice within traditional communities, especially by women by being the primary caregivers. This study aimed to perform ethnobiological survey of plants and animals used for the treatment of acute respiratory infections in children of a traditional community in the municipality of Barbalha, Ceará, Brazil.

METHODS

It is a descriptive exploratory study with a quantitative approach, developed in Sitio Santo Antonio, in the municipality of Barbalha, Ceará, Brazil. As a tool for data collection, was applied a questionnaire and a semi-structured interview. Data analysis used descriptive statistics (simple and percentage rate) and the Relative Frequency of Citation.

RESULTS

The research included a total of 54 informants. In total, there were 38 species cited. According to the Relative Frequency of Citation the following species were the most cited: Ocimum basilicum L. (0.59), Eucalyptus globulus Labili (0.59), Plectranthus amboinicus (L.) Spreng (0.42), Hyptis suaveolens (L.) Poit. (0.24), Allium aescalonicum L. (0.22) and Mentha arvensis L. (0.18). Among the symptoms mentioned by the research subjects to treat the acute respiratory infections in childhood, there were: fever; cough; coughing with secretions; sore throat; hoarseness; tiredness; nasal congestion.

CONCLUSIONS

It is important the knowledge about the usefulness of natural resources as alternative practices in diseases treatment, seeking to rescue popular knowledge used in the traditional community and fomenting the need to consider cultural aspects in the full practice to children's health care.

Effects of the Hyptis martiusii Benth. leaf essential oil and 1,8-cineole (eucalyptol) on the central nervous system of mice

The aim of this study was to characterize the central effects of the Hyptis martiusii leaf essential oil (OEHM) and 1,8-cineole (eucalyptol) using behavioral animal models. Gas chromatography coupled to mass spectrometry (GC/MS) was used to characterize the chemical compounds present in the OEHM. For the behavioral tests, female Swiss mice treated with the OEHM (25, 50, 100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) were used and subjected to the following tests: open field, elevated cross maze, rotarod, sodium pentobarbital- or ethyl ether-induced sleep time, pentylenetetrazol-induced convulsions, haloperidol-induced catalepsy, and ketamine-induced hyperkinesia. GC/MS analysis identified 20 constituents with the majority of them being monoterpenes and sesquiterpenes, with eucalyptol (1,8-cineol), the major sample compound (25.93%), standing out. The results showed the OEHM (25, 50 100 and 200 mg/kg, i.p.) and its major compound (50 mg/kg, i.p.) reduced animal motility in the open field test, increased pentobarbital- and ethyl ether-induced sleep time, as well as death latency in the pentylenetetrazole-induced convulsion model. However, the tested compounds were devoid of anxiolytic-like and myorelaxant activity. In addition, the OEHM (100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) potentiated haloperidol-induced catalepsy and reduced ketamine-induced hyperkinesia. Taken together, the results suggest the OEHM has important hypnotic-sedative and antipsychotic-like effects, which appear to be due to the monoterpene 1,8-cineole, the major compound identified in the essential oil.

Antiulcerogenic activity of the hydroalcoholic extract of leaves of Annona muricata Linnaeus in mice

Annona muricata Linnaeus, popularly known as “graviola” and also called soursop, is a species typical of countries with a tropical climate, and it is used in folk medicine as an anticancer, analgesic and antispasmodic agent. The aim of the present study was to validate the gastroprotective activity of the hydroalcoholic extract of the leaves of A. muricata (HEAM) and to investigate the underlying mechanisms of action for this effect. Gastric lesions were induced in mice by absolute ethanol, acidified ethanol or indomethacin. Before, the animals were pretreated with saline, omeprazole or HEAM orally at doses of 50–400 mg/kg. To determine the mechanism of action of the extract, we investigated, using specific inhibitors, the involvement of nitric oxide (NO), prostaglandins (PGEs), ATP-dependent K⁺ channels and α2-noradrenergic receptors. HEAM showed significant antiulcer activity against lesions induced by absolute ethanol, acidified ethanol or indomethacin, which was mediated by endogenous gastric prostaglandins.